Biological action of inosine analogs in Leishmania and Trypanosoma spp.

Previous investigations have suggested that inosine analogs would be good models for the development of chemotherapeutic agents active against pathogenic hemoflagellates. We have systematically modified the five-membered heterocyclic ring of six inosine analogs and tested them for their antiprotozoal activities and toxicity to a mammalian cell line. All six analogs were very active against the three protozoan pathogens Leishmania donovani, Trypanosoma cruzi, and Trypanosoma gambiense. Two of the six, 9-deazainosine and allopurinol ribonucleoside, had very little toxicity for mouse L cells and offer promise as potential chemotherapeutic agents.